[VAC] Shurflo Pump Question

[soule <soule@xxxxxxxxxxx>]

The discussions about winterizing and draining the water tank reminded
me to ask about an odd problem I am having with my 11-year-old Shurflo
model 2088 pump.  In order to get rid of stale water tank odors, I
filled the tank, added some bleach, left it overnight and pumped the
tank out. I did this a couple of times and each time I ran into the same
problem.   When I turn the pump on, it runs fine and will pressurize the
system if the faucets are closed.  When I leave it on for the long time
required to empty the tank, it will run for about 15 minutes and then
shut off by itself, even though the system is wide open and not
pressurized.  If I wait 15 minutes and turn the pump back on, it again
runs perfectly.  It's as if the pump is overheating (I have not checked
to see if it feels particularly hot) and tripping a self-resetting high
temperature limit switch.  As far as I can see from the Shurflo
brochure, the pump does not seem to have this type of thermal
protection.  Can anyone tell me what's going on?

Lincoln Soule
1977 Tradewind